Roofing Costs Dec, 2016. Call Portland Roof and Deck for all your roofing and decking needs. 503.465.4940.Portland Roof and Deck is a small company with one or Two crews. We take great pride in our work. So where a bigger company will be faster at installing your new roof we will not cut any corners and stand behind all our work. Below is our roofing cost breakdown.Our basic roofing costs is as follows:$375 per square.single story homes with a roof pitch less than 5/12.1 layer of old roofing to be torn off.easy access to house for trailer.30 year Malarkey roofing with 30 lb felt, metal valleys, new metal drip and edge metal.Does not include repair of any dry-rot or sheeting replacement. ($70 per sheet)Site clean up from roof tear off.Other homes will need a site visit to determine price.Portland Roof and Deck.503.465.4940.